In a presentation and news conference on Monday that lasted more than two hours, Samsung Electronics Co. detailed the results of its investigation into Note 7 smartphones that overheated and burst into flames last year.

First, InvenSense stock rose almost 30% in a single day on Dec. 9, 2016, as Reuters reported that TDK had offered $12 per share to purchase the smaller company. That offer would have reflected a 45% premium to InvenSense’s opening price that day, but still only 3% above its 52-week high set around the same time a year earlier.